Obstructive Sleep Apnea (OSA), a highly prevalent, under-diagnosed condition is responsible for more mortality and morbidity than any other sleep disorder and has been identified as a major public health concern. Pediatric OSA is also widespread with an estimated prevalence of approximately 2% and is increasingly recognized as a significant cause of morbidity in children. There is a growing demand for validated, in-home assessment methods for pediatric OSA for diagnostic and treatment outcome evaluations and to facilitate large epidemiological studies. Accurate assessment of the severity of pediatric OSA is also required to identify children at risk for postoperative complications following tonsillectomy and adenoidectomy, the most common treatment for childhood OSA. The Apnea Risk Evaluation System (ARES) was designed by Advanced Brain Monitoring to incorporate existing knowledge on sleep-disordered breathing into an easy-to-administer in-home diagnostic system for SA that employs a multivariate approach, uniquely combining physiological data acquired during sleep with anthropomorphic and clinical information obtained from a standardized questionnaire. The ARES integrates an easily applied, single site (forehead) Unicorder to record physiological signals during sleep with automated identification of abnormal respiratory events to quantify severity of OSA. The goal of this proposal is to modify the ARES to meet the demand for accurate diagnosis of pediatric OSA. In Phase I, the investigators propose that the ARES be evaluated in a population of thirty patients between the ages of 13 and 18 referred to a sleep laboratory for OSA assessment. This age group was selected for the Phase I feasibility study because the head sizes of teens are sufficiently similar to adults to assess the limitations of the ARES Unicorder as currently designed. In addition, establishing feasibility for the use of the ARES in teens would be an important accomplishment given the dramatic rise in obesity and asthma (two important OSA risk factors) in this age group. The goals for Phase II will be to study a large population of children and to modify the ARES Unicorder to accommodate the developmental range of forehead shapes and sizes for children under the age of 13. [unreadable] [unreadable] [unreadable]